Investigation on permeability and moisture management properties of different denim fabrics after repeated laundering

The physiological comfort determined by air permeability and moisture management properties of fabrics is influenced by various constructional parameters of the fabric which give woven fabric a porous structure. Evaporation of sweat during wear has the potential to cool the body besides restricting the additional weight of sweat being absorbed by the fabric. In this study, comfort characteristics of denim fabrics with different weft yarn of cotton, polyester and core spun Lycra have been discussed. Effect of enzyme washing and repeated laundering on air permeability, moisture management and drying rate has also been discussed. It was observed that air permeability and water vapour permeability of unwashed denim fabrics with cotton weft yarn are significantly higher than the fabric with polyester and Lycra cotton weft yarns. The wetting time is higher for cotton and Lycra cotton yarn fabrics. One-way transport index is highest for Lycra cotton weft fabrics and lowest for fabrics with polyester weft. Fabrics with polyester weft yarns show highest spreading rate, spreading radius and drying rate due to better wicking and hydrophobic nature of polyester fibres.     

不同混纺比甲壳素纤维/长绒棉混纺织物性能测试与分析

 用自纺的五种不同混纺比的19.5tex甲壳素/棉混纺纱织成同规格的织物,测定混纺织物的强伸度、pH值、刚柔性、透湿性、透气性、导湿性等,分析混纺比对混纺织物性能的影响。实验结果表明, 10/90甲/棉混纺织物的经纬向强力最大,芯吸性导湿性最好,20/80甲/棉混纺织物的透湿性最好,50/50甲/棉混纺织物的抗弯刚度最大,透气性最好。混纺织物的抗弯刚度和纬向强力及导湿性与混纺比显著相关。从穿着舒适性和纱线织物性能等几方面综合考虑, 20/80的甲/棉混纺织物较实用,而30/70的甲/棉混纺比例各方面性能较差。     

Studies on cotton-acrylic bulked yarns produced from different spinning technologies. Part II: fabric characteristics

The present work is concerned with the study of the characteristics of plain woven fabric produced with cotton-acrylic high-bulk yarns from different spinning technologies. The effects of different factors, namely spinning technologies (ring, rotor and DREF-II, i.e. Group A fabrics), position of shrinkable acrylic feed sliver in DREF-II friction spinning system (Group B fabrics) and proportion of shrinkable acrylic core fibre in core-sheath type DREF-III friction spun yarns (Group C fabrics) on various properties of cotton-acrylic blended bulked yarn fabrics have been reported. The influence of these three variables on the mechanical, handle and comfort properties of fabrics have been studied. The properties of fabrics made of bulked yarns from different spinning technologies are found to be different from the normal 100% cotton yarn fabrics in all respect. Even though the bulked yarns were used only in weft direction, the fabrics with modified yarn structures show appreciable improvement in thermal resistance, moisture vapour transmission, wicking and air permeability. The bending rigidity of the fabrics in weft direction also reduced with improvement in crease recovery in weft direction.     

Effect of cotton fiber and yarn characteristics on color variation in woven fabric dyed with vat dyes

The aim of this study was to investigate the effect of cotton fiber and yarn characteristics on the color variation of woven fabrics dyed with vat dyes. A fabric length of 31?m was woven so that each meter of the fabric comprised weft yarns of slightly different cotton fiber or yarn characteristics as compared to the other. The woven fabric was pretreated and dyed with vat dyes using industrial-scale, pad-dry-chemical-pad-steam process. After dyeing it was found that the fabric containing weft yarns made from cotton with higher reflectance (Rd) values gave poor color strength as compared to that of lower Rd values. Fabric comprising combed weft yarns showed better color depth (K/S) values as compared to that comprising carded weft yarns made from the same raw cotton. Furthermore, the fabric comprising finer- or lower-twist weft yarns gave higher color depth as compared to that with coarser or higher-twist weft yarns. It was concluded that slight variations in the cotton or yarn characteristics in the weft yarns could result in significant shade variations in the vat-dyed fabric.     

Mathematical model to predict vertical wicking behaviour. Part II: flow through woven fabric

The aim of the paper is to develop a mathematical model to predict vertical wicking behaviour of woven fabric. The first part of this series (Part I) has dealt with the mathematical model for predicting vertical wicking through yarn. In this part a model has been proposed to predict vertical wicking of the woven fabric, based on the developed yarn model. In order to model the flow through woven fabric along with the vertical flow through liquid carrying threads, the horizontal flow through transverse threads has also been taken into account. A simplified fabric geometrical concept (inclined tube geometry) and Peirce geometry for plain woven fabric have been used to define the fabric structure. Warp and weft linear density, fabric sett and yarn crimp have been considered in the fabric modelling. The theoretical wicking values of the yarn and fabric made from that yarn have been compared. Experimental verification of the model has been carried out using polyester and polypropylene fabrics. The model is found to predict the wicking height with time through the yarns and fabrics with reasonable accuracy.     

Coolmax纤维含量对交织物舒适性能的影响

对5种Coolmax／棉交织织物的吸水性、透湿性、透气性进行了测试,建立了Coolmax纤维含量与织物经向、纬向芯吸高度,透湿量、透气率的回归方程。结果表明随着纬纱中Coolmax纤维含量的增加,Coolmax／棉交织织物的吸水性、透湿性和透气性越好。     

Effect of structural parameters of porous yarns and fabric on air permeability and moisture transfer of double-face woven fabrics

In this study, effect of fabric structural parameters of double-face woven fabrics including kind of porous yarn namely micro-porous yarn and hollow yarn, hole size of hollow yarn, percentage of these yarns in double-face woven fabric structure, and finally weft density on air permeability and moisture transfer of woven fabrics was evaluated. These yarns were produced by using water-soluble continuous polyvinyl alcohol filaments as core part for hollow yarns and as doubling yarn in micro-porous yarn. Results revealed the effect of kind of porous yarn, hole size of hollow yarn, and weft density on air permeability and moisture transfer of woven fabrics. The percentage of porous yarns as weft did not show obvious trend. Analysis of variance was used to study the effect of these variables on air permeability and moisture transfer of double-face woven fabrics statistically.     

Comfort properties of bamboo/cotton blended knitted fabrics produced from rotor spun yarns

The comfort characteristics of bamboo/cotton-blended knitted fabrics made from rotor-spun yarns were studied in this research work. Five different blend proportions namely 100% bamboo, 100% cotton, 50:50 cotton:bamboo, 70:30 cotton:bamboo and 30:70 cotton:bamboo were used to produce rotor-spun yarns of 30^sNe_c. The yarn samples developed out of these different blend proportions were evaluated for yarn strength and elongation, yarn unevenness, yarn imperfections and used to produce single-jersey-knitted fabrics. All the fabric samples were dyed and finished. Fabric samples were evaluated for geometrical properties such as course/inch, wales/inch, stitch density and thickness apart from measuring comfort properties such as airpermeability, thermal conductivity, thermal resistance and water vapour permeability. The results indicated that 50/50 bamboo/cotton-blended knits have comparable fabric quality in terms of comfort properties with respect to 100% bamboo fabrics.     

Study on effect of blend ratio on thermal comfort properties of cotton/nylon-blended fabrics with high-performance Kermel fibre

This study presents the thermal comfort properties of woven fabrics made of Kermel, cotton/nylon and cotton/nylon /Kermel-blended yarns. Our aim in this study is to combine the high comfort properties of cotton/nylon fibres with high thermal protective properties of Kermel fibre in different woven fabrics. Thus, Kermel (100%), cotton/nylon (50:50) and four blends of the 50% cotton fibres with nylon and Kermel (40:10, 30:20, 20:30 and 10:40) were spun on a ring-spinning frame and twisted into two-folded yarns with the same yarn count of 30/2(Ne) and twist level of 560 TPM. Using the produced yarns, woven fabrics with identical characteristic and structure were also produced. Then, the thermal comfort and physical properties of fabrics were studied in terms of fabric porosity, thermal resistance, thermal conductivity, water vapour resistance and air permeability. The results show that the porosity, air permeability and thermal resistance increase with Kermel fibre blend ratio. Conversely, the water vapour resistance decreases with increase of Kermel fibre blend ratio up to 40%, while 100% Kermel-woven fabric exhibits a higher water vapour resistance value. Nevertheless, the thermal conductivity of cotton/nylon-blended Kermel woven fabric is unchanged with increase of Kermel fibre blend ratio up to 40%, whereas at 100% Kermel fibre blend ratio, the lowest thermal conductivity is obtained. The obtained results implied that woven fabric produced from cotton/nylon (50/10) blended with 40% Kermel fibre resulted in proper thermal comfort properties.     

组织结构对UHMWPE短纤纱织物防刺性能的影响

UHMWPE短纤纱具有优秀的抗切割性与较好的树脂浸润性,非常适用于制作防刺材料。文章试织了12种不同织物规格的试样,进行准静态穿刺实验,探究5种因素(组织、紧度、纱线线密度、经纬密和面密度)对织物防刺性能的影响,并比较不同穿刺角度下织物防刺性能的差异。结果表明:与方平织物与接结双层织物相比,平纹织物的防刺性能最好;同种经纬密或同紧度下,粗特纱织制的平纹织物防刺性能好;随着经密增加,紧度增加,面密度增加,防刺性能逐渐增加,但织物过于紧密时,防刺性能反而降低;平纹织物的穿刺性能具有各向异性,经纬向的防刺性能优于45°方向。     

Preparation,characterisation of bamboo charcoal particles and the effect of their application on thermo-physiological comfort properties of woven fabrics

Abstract

Bamboo charcoal particles were prepared at micro level and applied on three types of woven fabric, namely 100% cotton, 100% polyester and 65/35 p/c blend. The thermo-physiological comfort properties such as wetting, wicking, water vapour permeability, air permeability and thermal resistance of the control and treated fabrics were investigated to study the effect of bamboo charcoal particles application on these fabrics. The results reveal that the bamboo charcoal treated fabrics show a good improvement in wetting, wicking and water vapour permeability. The charcoal particle finished fabrics also showed a slight decrease in thermal resistance thereby contributing to a corresponding improvement in thermal conductivity with a reduction in air permeability when compared with the control fabrics. The bamboo charcoal treated fabrics showed a good fastness to washing thus exhibiting good durability on the fabrics selected for the study. Also, the charcoal treated fabrics revealed a higher wickability than the control fabrics even after 20 washes.     

Development of woven stretch fabrics and analysis on handle,stretch, and pressure comfort

Twelve stretchable fabrics are woven in two sets with one set in 50^s and 60^s 100% cotton in warp and 40^s, 50^s, and 60^s cotton core spun lycra yarn in weft and another set with 2/75 and 2/120?Nm silk in warp with 40^s, 50^s, and 60^s cotton core spun lycra yarn in weft. Hundred percent cotton sari blouse materials commercially available in the market are also included for a comparative study of pressure distribution between cotton core spun lycra fabrics and cotton blouse materials. The influence of fabric specification on total hand value (THV), stretch properties, and pressure comfort is analyzed. The effects of body shape and fabric mechanical properties on garment pressure are also analyzed. The results indicated that the finer counts of cotton core spun lycra woven with cotton and silk to elasticize fabrics provided improved hand feel, stretch, and pressure comfort values. The average pressure value of the samples at the major pressure points with the cotton/cotton core spun lycra samples and silk/cotton core spun lycra samples is lower than 100% cotton samples’ fabric physical properties, stretch properties, mechanical properties, and THV significantly influenced the pressure distribution and comfort of garments.     

Total porosity,theoretical analysis,and prediction of the air permeability of woven fabrics

Air permeability is one of the most important properties of textile materials that ensure their comfort. For many materials for technical applications (filters, sails, vacuum cleaners, parachutes, etc.), this is one of the main properties that determine their quality. The air permeability of woven textile fabrics depends on many parameters of fabric. Thus, the determination of air permeability of woven fabric is highly complex and difficult. In this study, we attempted to establish a theoretical model for the porosity and predicted the air permeability of woven fabrics. A theoretical model was created to predict the total porosity and the air permeability of a fabric structure depending on the geometrical parameters such as pore size, warp density, weft density, fabric thickness, number of yarn, diameter of yarn, and fiber density. For the purpose, a theoretical model of porous systems on D’Arcy’s law was used, and the validity of the model was confirmed by experimental results using 100% cotton and 97/3 cotton/lycra woven fabrics. Since the amount of air passing through both the pores between yarns and the interstices in the fibers constituting the yarn structure was calculated, theoretical values of air permeability were obtained very close to the experimental values.     

织物结构对热敏变色纤维织物呈色效果的影响

为了研究织物结构对热敏变色纤维织物呈色效果的影响,经纱采用棉纱,纬纱选用热敏变色粘胶长丝纱,设计织造了5种不同组织结构的机织物,对其变色前后的颜色空间值、三刺激值、彩度以及白度等颜色指标进行了测试,并分析了织物组织及纬密对热敏变色纤维织物呈色效果的影响及显著性。研究结果表明:织物组织对织物明度、彩度和色相偏红程度影响显著,对白度影响不显著。平纹织物的明度和白度最高,缎纹织物的彩度和色相偏红程度最高;织物纬密对明度影响显著,对彩度、白度、色相偏红程度影响不显著,随着纬密的增加,织物色相偏红程度呈增加趋势。研究结果对热敏变色纤维织物的设计开发具有一定的参考价值。     

Acoustic performance of woven fabrics in relation to structural parameters and air permeability

This work deals with the study of the acoustic characteristics of woven fabrics in relation to fabric structural parameters and air permeability. In order to achieve the objectives of the research, sound absorption coefficient of woven fabric samples was determined via impedance tube method. Samples with various pick densities and yarn twist were used. The effect of fabric thickness was analyzed using three and six layered test samples. Results showed that, while for all samples the minimum values of sound absorption were observed at frequency bands of 250 and 2000?Hz, the maximum sound absorption occurred at the frequency of 1000?Hz. Results also indicated that fabrics woven at pick density of 30?thread/cm exhibited higher sound absorption than fabrics woven at other pick densities. It was found that, noise reduction coefficient of three and six layered samples, woven at low pick densities showed significant increases in comparison to those woven at high pick densities. It was also established that samples woven with lower weft yarn twist absorb sound wave more efficiently. It was concluded that fabric air permeability can be used as a criterion of sound absorption behavior of woven fabrics.     

Impact of structural variations in hollow yarn on heat and moisture transport properties of fabrics

The use of hollow/microporous yarns plays an important role in enhancing the thermo‐physiological comfort properties of fabrics. Depending on structural variations in hollow yarn, heat and moisture regulation behaviours of fabrics can be affected significantly. In this study, three types of hollow cotton yarn fabrics, produced by introducing polyvinyl alcohol (PVA) filament in the core, PVA staple fibres in the blend and PVA filament in doubling with cotton spun yarn, are studied. All three types of pre‐hollow yarns and reference yarns are made with a variation in spinning technique (single roving/double roving) to prepare eight single jersey knitted fabrics. The hollow/microporous structure of the yarn is created by dissolving the PVA fibres using hot washing of the fabrics. On overall evaluation of the fabric’s thermo‐physiological comfort properties, the doubled hollow yarn fabrics are found to be better than other fabrics. In general, thermal resistance, thermal absorptivity, wicking and drying properties of all types of hollow yarn fabrics increase after repeated laundering, while air permeability, water vapour permeability and water absorbency of hollow yarn fabrics mostly decrease. In contrast with fabrics made from yarn produced through single roving technique, use of double roving technique only improves fabric water vapour permeability.     

Elastic Recovery and Performance of Denim Fabric Prepared by Cotton/Lycra Core Spun Yarns

ABSTRACT

Elastic performance coefficient (EPC) and recovery behavior of denim fabrics prepared with cotton/lycra core spun stretch yarns have been presented in this article. The denim fabrics are woven as broken twill weaves in an air-jet weaving machine by the insertion of core spun yarns (lycra filament in core, cotton fiber on sheath) as weft and using 100% cotton yarns as warp. The effect of linear density and stretch percentage of the core spun weft yarns on tensile and recovery behavior of denim fabric have been investigated by employing full factorial design of experiments. It has been observed that the tensile strength and EPC of fabric increase with decrease in linear density and stretch percentage of the core spun stretch yarn. The immediate elastic recovery and delayed elastic recovery increase with decrease in linear density and stretch percentage of the yarns.     

Thermo-physiological comfort characteristics of polyester air-jet-textured and cotton-yarn fabrics

Air-jet-textured polyester yarns were produced using two feed yarns differing in filament fineness and number of filaments. By varying the overfed rates of feed yarns and changing their positions in core and effect, five textured yarns were produced. Woven fabrics were prepared using these textured yarns as weft and cotton yarns in warp. To study the effect of air-jet-texturing parameters on the thermo-physiological comfort characteristics of fabric, the woven fabrics were tested for thickness, thermal properties, transverse wicking and air permeability. It is observed that thermal conductivity and resistance of fabrics are not influenced by the texturing parameters/textured yarn structure. These properties are mainly dependent on the entrapped air present in fabrics. Thermal absorptivity is a transient phenomenon of heat flow reflecting that the ‘warm-cool feeling’ effect of fabrics depends on smoothness/roughness of fabric surface. Fabrics with smooth surfaces have higher thermal absorptivity values as they provide a large area of contact with human skin. The roughness of fabrics depends on the number of surface loops and filament fineness. Transverse wicking of fabrics depends on the size, continuity and alignment of the capillaries present in the core of textured yarns.     

高导湿仿真丝涤棉机织物的性能

采用超细涤纶长丝与长绒棉丝光纱交织,通过织物组织、经纬密度、织物紧度等参数设计开发出了高吸湿仿真丝涤棉双面机织物;并对织物进行了滴水扩散时间、水分蒸发速率、芯吸高度、吸水率、透湿量等吸湿导湿性能及光泽性测试分析。结果表明八枚缎纹组织、经纬密度400×320、总紧度85．35％的织物其吸湿导湿性能最强,光泽最好。     

The functionality of woven fabric from air-jet yarn from the mixture of CO/PA and CO/PES fibres in the weft direction

The purpose of presented research is to find out the influence of air-jet yarn from the mixture of CO/PA (50/50) and CO/PES (67/33) fibres on functionality of woven fabric in the plain weave.The first part of the study is directed to the mechanical and physical properties of air-jet yarns (16.7 tex) from CO/PA and CO/PES fibres, while the second part of the study focuses on permeability properties of fabrics with air-jet yarns in the weft. The results show that air-jet yarn in the weft direction influences on the water vapor transmission and thermal conduction increase and air permeability decrease.Incorporation of air-jet yarn in the weft direction also improves breaking extension level.The results of presented research also show that the incorporation of air-jet yarn in the weft has statistical important influence on thermal conduction, water-vapor and air permeability changes.